More than 832 people have been confirmed dead after a tsunami triggered by a magnitude 7.5 earthquake hit an Indonesian city on Friday.
Waves up to 3m (10ft) high swept through Palu on Sulawesi island.
Video on social media shows people screaming and fleeing in panic and a mosque among the buildings damaged.
Strong aftershocks continue to rock the city. Thousands of homes have collapsed, along with hospitals, hotels and shopping centres.
Rescue efforts are under way, though hampered by a major power cut. The main road to Palu has been blocked due to a landslide, and a key bridge brought down.
Indonesia’s disaster agency said at least 832 people had been killed, but the number is expected to rise.
“Many bodies were found along the shoreline because of the tsunami, but the numbers are still unknown,” Sutopo Purwo Nugroho, a spokesman for the agency, told Reuters.
“When the threat arose yesterday, people were still doing their activities on the beach and did not immediately run and they became victims,” he told a news briefing.
Some survived by climbing six metre (18 ft) trees to escape the huge waves, the spokesman said.
A less powerful quake earlier on Friday had killed at least one person and injured at least 10 in the smaller fishing town of Donggala.
In Palu, hundreds of people had been preparing for a beach festival that was due to start on Friday night.
The city’s main hospital was damaged in the quake, and TV footage showed dozens of injured people being treated outside in makeshift medical tents.
Detik-detik saat tsunami menerjang Pantai Palu pada 28/9/2018 sore pascagempa 7,7 SR mengguncang Donggala. Tinggi tsunami sekitar 3 meter. Permukiman di sekitar pantai hancur disapu tsunami. pic.twitter.com/GnxecozDKk
— Sutopo Purwo Nugroho (@Sutopo_PN) September 28, 2018
Palu and Donggala are home to more than 600,000 people. President Joko Widodo said on Saturday that troops were en route to the area to reinforce rescue teams and help retrieve bodies.
The main airport in Palu has been closed since the tsunami hit. A minister said the runway had been damaged but that it was hoped helicopters would still be able to land.
The country’s military is sending cargo planes of relief aid from the capital, Jakarta.
The earthquake hit just off central Sulawesi at a depth of 10km (6.2 miles) just before 18:00 (11:00 GMT), the US Geological Survey said.
A tsunami warning was issued, but lifted within the hour. Indonesia’s meteorological agency has been criticised for its response, but officials said the waves struck while the warning was in place.
Indonesia is prone to earthquakes because it lies on the Ring of Fire – the line of frequent quakes and volcanic eruptions that circles virtually the entire Pacific rim.
More than half of the world’s active volcanoes above sea level are part of the ring.
Just last month, a series of deadly earthquakes struck the Indonesian island of Lombok. The biggest, on 5 August, killed more than 460 people.